On the Scope of Trimethylaluminium-Promoted 1,2-Additions of ArZnX Reagents to Aldehydes
作者:Daniel Glynn、Jonathan Shannon、Simon Woodward
DOI:10.1002/chem.200901803
日期:2010.1.18
functionalised arylzinc halides to aromatic and aliphatic aldehydes is described by the use of aminoalcohol catalysis in the presence of AlMe3. The process is simple to carry out, uses only commercially available reagents/ligands and provides moderate to good (80–96 % ee) enantioselectivities for a wide range of substrates. Either commercial ArZnX reagents or those prepared in situ from low cost aryl bromides
通过在AlMe 3存在下使用氨基醇催化,描述了官能化的芳基卤化锌与芳族和脂族醛的不对称1,2-加成反应。该方法操作简单,仅使用市售试剂/配体,并能为多种底物提供中等至良好(80-96%ee)的对映选择性。可以使用市售的ArZnX试剂,也可以使用由低成本的芳基溴化物原位制备的试剂。在后一种情况下,可以耐受亲电官能团(CO 2 Et,CN)。该反应依赖于ArZnX和AlMe 3之间的快速交换,生成混合的有机金属物质,从而导致形成与经典“Noyori的“反”过渡状态。核磁共振监测和相关实验已被用来探测所提出的选择性过渡态的有效性。